WO 2011/160632 discloses benzodioxole and benzodioxepene heterocyclic compounds useful as PDE4 inhibitors as well as suitable methods for the preparation thereof.
WO 2008/104175 discloses benzodioxole and benzodioxepene heterocyclic compounds useful as PDE4 inhibitors as well as suitable methods for the preparation thereof.
WO 2008/077404 discloses substituted acetophenones useful as PDE4 inhibitors as well as suitable methods for the preparation thereof.
In the development of new drug candidates, it is highly desirable to have access to alternative methods for the preparation of the drug candidates, as some efficient small-scale synthesis may turn out to be difficult to up-scale to production scale quantities. Also, small-scale syntheses may involve reagents and solvents which are not feasible to utilize at a production scale level.
Hence, it is an object of the present invention to provide alternative methods for the preparation of 1,3-benzodioxole heterocyclic compounds of the type disclosed in WO 2011/160632, insofar that such alternative methods provide advantages with respect to one or more features like the number of reactions steps, purity, yield, ease of purification, process economy, availability of starting materials and reagents, safety, predictability, etc.